diff --git a/tools/sort_map.py b/tools/sort_map.py
new file mode 100644
index 000000000..020ca94b6
--- /dev/null
+++ b/tools/sort_map.py
@@ -0,0 +1,103 @@
+#!/usr/bin/env python3
+
+import sys
+import re
+
+encoding = 'utf-8'
+
+def total_bank_size(type):
+	# used to output the size of EMPTY banks
+	sizes = {
+		'ROM0':  0x4000, # 0000–3FFF
+		'ROMX':  0x4000, # 4000–7FFF
+		'VRAM':  0x2000, # 8000–9FFF
+		'SRAM':  0x2000, # A000-BFFF
+		'WRAM0': 0x1000, # C000-CFFF
+		'WRAMX': 0x1000, # D000-DFFF
+		                 # E000-FDFF: echo RAM
+		'OAM':     0xA0, # FE00-FE9F
+		                 # FEA0-FEFF: unusable
+		                 # FF00-FF7F: hardware I/O registers
+		'HRAM':    0x80, # FF80-FFFF
+	}
+	return sizes[type]
+
+def sorted_mapfile(input):
+	bank_rx = re.compile(r'^([A-Z]+) Bank #([0-9]+)')
+	section_rx = re.compile(r' +SECTION: \$([0-9A-F]+)(?:-\$([0-9A-F]+))? \(\$([0-9A-F]+) bytes\) \["(.+)"\]')
+	label_rx = re.compile(r' +\$([0-9A-F]+) = (.+)')
+	slack_rx = re.compile(r' +SLACK: \$([0-9A-F]+) bytes')
+
+	bank_type = None
+	bank_number = None
+	bank_size = 0
+	bank_queue = []
+	section_queue = []
+
+	for line in input:
+
+		if line.startswith('  EMPTY'):
+			# empty banks have their entire capacity as slack
+			line = '    SLACK: $%04X bytes\n' % total_bank_size(bank_type)
+
+		x = re.match(bank_rx, line)
+		if x:
+			# start a new bank
+			bank_type = x.group(1)
+			bank_number = '%02X' % int(x.group(2))
+			if bank_type == 'ROM':
+				bank_type = 'ROM0' if bank_number == '00' else 'ROMX'
+			if bank_type == 'WRAM':
+				bank_type = 'WRAM0' if bank_number == '00' else 'WRAMX'
+			bank_size = 0
+			bank_queue.clear()
+			section_queue.clear()
+			continue
+
+		x = re.match(section_rx, line)
+		if x:
+			# finish current section
+			bank_queue.extend(sorted(section_queue))
+			# start a new section
+			start = x.group(1)
+			end = x.group(2) or start
+			size = x.group(3).zfill(4)
+			name = x.group(4)
+			bank_size += int(size, 16)
+			bank_queue.append('; %s:%s-%s ($%s) %s\n' % (bank_number, start, end, size, name))
+			section_queue.clear()
+			continue
+
+		x = re.match(label_rx, line)
+		if x:
+			# add label to section
+			address = x.group(1)
+			label = x.group(2)
+			section_queue.append('%s:%s %s\n' % (bank_number, address, label))
+			continue
+
+		x = re.match(slack_rx, line)
+		if x:
+			# finish current section
+			bank_queue.extend(sorted(section_queue))
+			# finish current bank
+			slack = int(x.group(1), 16)
+			yield '; %s $%s ($%s) ($%04X free)\n' % (bank_type, bank_number, bank_size, slack)
+			yield from bank_queue
+			continue
+
+def main():
+	if len(sys.argv) < 3:
+		print('Usage: %s pokecrystal.map sorted.sym' % sys.argv[0], file=sys.stderr)
+		sys.exit(1)
+	input_filename = sys.argv[1]
+	output_filename = sys.argv[2]
+	with open(input_filename, 'r', encoding=encoding) as infile:
+		input = infile.readlines()
+		output = sorted_mapfile(input)
+	with open(output_filename, 'w', encoding=encoding) as outfile:
+		for line in output:
+			outfile.write(line)
+
+if __name__ == '__main__':
+	main()